Information recording method and apparatus with additional recording function

ABSTRACT

An information recording apparatus includes: a unit for applying a predetermined processing to record information divided into error correction units and generating processed record information including a plurality of record units; and a unit for recording the processed record information on an information record medium; a unit for recording, after the recording of the processed record information, predetermined dummy information of an information amount corresponding for the plurality of record units, on the information record medium, subsequent to the processed record information recorded.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention is related with an information recordingmethod and apparatus for adding and recording new record informationsubsequent to old record information recorded previously on a recordableinformation record medium, such as a high-density optical disc and thelike, represented by DVD-R (DVD-Recordable) on which the information canbe recorded only once.

[0003] 2. Description of the Related Art

[0004] Generally, in the recordable information record medium on whichthe information can be recorded only once, when it is tried to lateroverwrite the new record information to an area on which the old recordinformation has once been recorded, both the old record information andthe new record information may be broken.

[0005] In the information recording method and apparatus for adding andrecording the new record information to this kind of the recordableinformation record medium, when recording the new record informationsubsequent to the old record information, a linking area (or a boundaryarea) corresponding to an information amount of a single errorcorrection unit, such as an ECC (Error Correcting Code) block and thelike according to the error correcting system used therein, wasconventionally provided at the linking or boundary portion of the oldrecord information and the new record information. In the linking area,a meaningless dummy information or a predetermined RF (Radio Frequency)signal is recorded at a last portion of the old record information or afirst portion of the new record information, and then the new recordinformation is recorded thereon.

[0006] The reason why this linking portion is provided is as follows. Ifthe linking portion is not provided, at the time of consecutivelyreproducing the new record information, recorded later, as well as theold record information, the RF signal may be discontinuous at theboundary of the record area of the old record information and the recordarea of the new record information, thereby resulting in an unstablefocus servo or tracking servo control.

[0007] The reasons why the linking portion is provided for the datacapacity corresponding to one ECC block is and why the meaningless dummyinformation or the like is recorded therein are explained below. In theconventional error correcting process, the error correction is performedby each error correction unit. If the new record information is recordedfrom the middle of the error correction unit, the appropriate errorcorrection can not be performed for a head portion of the new recordinformation, at the time of consecutively reproducing the old recordinformation and the new record information later. Thus, theappropriately continuous reproduction can not be performed. In thisregard, if the meaningless dummy information or the predetermined RFsignal is recorded for one ECC block within the linking area asmentioned above, it is possible to reproduce the old record informationand the new record information continuously by skipping the linking areaand reproduce the new record information from an ECC block next to thelinking portion, even though the overlapped portion of the old recordinformation and the new record information in the linking portion isbroken.

[0008] Further, another reason why the linking area is provided is asfollows. If the new record information is recorded to follow the oldrecord information without providing the linking area, both of the oldrecord information and the new record information may be broken at theoverlapped portion of them. In that case, if the information brokenportion exceeds a single error correction unit, it is impossible torecover the broken record information. For the reasons described above,the linking area is provided at the linking or boundary portion of theold record data and the new record data.

[0009] However, the conventional error correction unit has relativelylarge capacity, for example, approximately 32 K bytes, and this area isentirely filled with meaningless information having no relation with therecorded information. Therefore, there is a problem that it results inan extremely ineffective use of the high-density disk or the like, whichneeds to record a large amount of information.

SUMMARY OF THE INVENTION

[0010] The present invention is proposed from the viewpoint of the abovementioned problems. It is therefore an object of the present inventionto provide an information recording method and apparatus, which can addand record new record information with effectively utilizing a recordarea on an information record medium and accurately perform aconsecutive and successive reproduction of old record information andnew record information.

[0011] According to one aspect of the present invention, there isprovided an information recording method including the steps of:applying a predetermined processing to record information divided intoerror correction units and generating processed record informationincluding a plurality of record units; recording the processed recordinformation on an information record medium; and recording, after therecording of the processed record information, predetermined dummyinformation for an information amount corresponding to the plurality ofrecord units, on the information record medium, subsequent to theprocessed record information recorded.

[0012] In accordance with the method thus designed, a predeterminedprocessing is applied to record information to generate processed recordinformation. Then, the processed record information is recorded on theinformation record medium, and dummy information is recorded for theinformation amount of plural record units, subsequent to the processedrecord information thus recorded. Therefore, in a case of consecutivelyreproducing the processed record information, by replacing thereproduced dummy information with pre-set data, it is possible toperform the consecutive reproduction while carrying out the errorcorrection within a range of an error correction capability.

[0013] The method may further include the step of overwriting dummyinformation including the steps of: detecting a head position of an olddummy information previously recorded on the information record medium;and recording new dummy information on the information record medium,based on the detected head position, such that a total informationamount of the old dummy information after the recording of the new dummyinformation and the new dummy information recorded is no more than aninformation amount of one error correction unit.

[0014] In accordance with the method thus designed, a head position ofan old dummy information previously recorded on the information recordmedium is detected. Then, new dummy information is recorded on theinformation record medium, based on the detected head position, suchthat a total information amount of the old dummy information after therecording of the new dummy information and the new dummy informationrecorded is no more than an information amount of one error correctionunit.

[0015] Further, the processed record information recording step mayfurther include the step of recording new record information on theinformation recording medium from a position subsequent to the new dummyinformation recorded. Still further, the dummy information recordingstep may record the new dummy information over a part of the old dummyinformation previously recorded.

[0016] Thus, the new record information is added and recorded subsequentto dummy information whose content is known in advance. As a result, ina case of consecutively reproducing old record information recordedprior to the old dummy information and the new record information, it ispossible to perform the consecutive reproduction while carrying out theerror correction within the range of the error correction capability.Since the total information amount of the old dummy information and thenew dummy information is no more than that of one error correction unit,within the linking portion of the old record information and the newrecord information, it is possible to make an area used for recordingthe record information larger, as compared with the case of providing alinking portion corresponding to one error correction unit. In addition,since the recording area of the old and new dummy information, which maylikely be broken due to the overwriting, is smaller than a single errorcorrection unit, the error correction of the neighboring recordinformation is not disturbed. As a result, it is possible to accuratelyperform the consecutive reproduction.

[0017] Alternatively, the processed record information recording stepmay include the steps of: detecting a head position of the dummyinformation previously recorded on the information record medium;determining a recording start position from which new record informationis recorded on the basis of the detected head position of the dummyinformation and an information amount in a single error correction blockwhich is a minimum information unit of error correction; calculating aninformation removal amount corresponding to an information capacity inan area from the head position to the recording start position; removingthe record information corresponding to the calculated removal amountfrom a head of the record information so as to produce an actual recordinformation; and recording the actual record information from therecording start position onto the information recording medium.

[0018] In accordance with the method thus designed, an informationamount of the new record information at the head portion, which maylikely be broken at the time of recording the new record information, isno more than the correction block that is the minimum unit for an errorcorrecting process. Accordingly, it is possible to minimize thedeterioration of the error correction performance in consecutivelyreproducing the old record information and the new record information.As a result, even if there is dust or the like on the information recordmedium at the time of reproduction, it is possible to achieve reliableerror correction performance. Moreover, there is apparently no existenceof the linking portion between the old record information and the newrecord information because the dummy information portion recordedpreviously and the new record information, which is likely be broken,are restorable by the error correction. As a result, it is possible tomake the area used for recording the record information larger, ascompared with the case of providing the linking portion corresponding tothe entire error correction unit.

[0019] Also, the recording start position determining step may determinethe recording start position within an area where the dummy informationis previously recorded. By this, new record information is recordedsubsequent to the dummy information having a content that is known inadvance. As a result, it is possible to make the deterioration of theerror correction performance smaller, when consecutively reproducing theold record information and the new record information.

[0020] According to another aspect of the present invention, there isprovided an information recording apparatus including: a unit forapplying a predetermined processing to record information divided intoerror correction units and generating processed record informationincluding a plurality of record units; a unit for recording theprocessed record information on an information record medium; and a unitfor recording, after the recording of the processed record information,predetermined dummy information of an information amount correspondingfor the plurality of record units, on the information record medium,subsequent to the processed record information recorded.

[0021] The apparatus may further include a unit means for overwritingdummy information including: a unit for detecting a head position of anold dummy information previously recorded on the information recordmedium; and a unit for recording new dummy information on theinformation record medium, based on the detected head position, suchthat a total information amount of the old dummy information after therecording of the new dummy information and the new dummy informationrecorded is no more than an information amount of one error correctionunit.

[0022] Still further, the processed record information recording unitmay further include a unit for recording new record information on theinformation recording medium from a position subsequent to the new dummyinformation recorded. Also, the dummy information recording unit mayrecord the new dummy information over a part of the old dummyinformation previously recorded.

[0023] Alternatively, the apparatus may be so configured that theprocessed record information recording unit includes: a unit fordetecting a head position of the dummy information previously recordedon the information record medium; a unit for determining a recordingstart position from which the new record information is recorded on thebasis of the detected head position of the dummy information; a unit forcalculating an information removal amount corresponding to aninformation capacity in an area from the head position to the recordingstart position; a unit for removing the record information correspondingto the calculated removal amount from a head of the record informationto produce an actual record information; and a unit for recording theactual record information from the recording start position onto theinformation recording medium. Further, the recording start positiondetermining unit may determine the recording start position within anarea where the dummy information is previously recorded.

[0024] The nature, utility, and further features of this invention willbe more clearly apparent from the following detailed description withrespect to preferred embodiments of the invention when read inconjunction with the accompanying drawings briefly described below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025]FIG. 1A is a view showing a data structure of record informationin an embodiment,

[0026]FIG. 1B is a view showing a configuration of an ECC block in therecord information of the embodiment,

[0027]FIG. 2 is a view showing a physical format of the recordinformation of the embodiment,

[0028]FIG. 3 is a block diagram showing a schematic configuration of aninformation recording apparatus according to the present invention,

[0029]FIG. 4 is a flow chart showing a process according to a firstembodiment of an information recording operation;

[0030]FIG. 5 is a view explaining the recording manner of the recordinformation by the process of the first embodiment;

[0031]FIG. 6 is a flow chart showing a process according to a secondembodiment of the information recording operation; and

[0032]FIG. 7 is a view explaining the recording manner of the recordinformation by the process of the second embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Next, preferred embodiments of the present invention areexplained with reference to the drawings. The following embodimentsexplain the embodiments in which the present invention is applied to aninformation recording apparatus for recording information on a DVD-R.

[0034] (I) Embodiment of Record Format

[0035] At first, a generally physical format for recording recordinformation on the DVD-R and an error correcting process in the recordinformation are explained with reference to FIGS. 1 and 2.

[0036] The error correcting process in the DVD-R of this embodiment andan ECC block, serving as an error correction unit, in the errorcorrecting process are firstly explained with reference to FIGS. 1A and1B.

[0037] Generally, the record information recorded on the DVD-R has aphysical structure including a plurality of data sectors 20 shown inFIG. 1A. One data sector 20 is composed of, from a head portion thereof,an ID information 21 indicative of a start position of the data sector20, an ID information error correction code (IEC) 22 for correctingerrors of the ID information 21, a reserve data 23, a data 24 which isthe main data to be recorded, and an error detection code (EDC) 25 fordetecting errors in the data 24. The record information to be recordedis constituted by a continuous plurality of the data sectors 20.

[0038] Next, process for constituting the ECC block by the data sectors20 are explained with reference to FIG. 1B.

[0039] When constituting an ECC block 30 by the data sectors 20, onedata sector 20 is firstly divided into plural blocks each of which is172 bytes data, as shown in FIG. 1B, and each divided data (this ishereafter referred to as a “data block 33”) is arranged in a verticaldirection (refer to the left side of FIG. 1B). At this time, the datablocks 33 are arranged in 12 lines in the vertical direction.

[0040] For each data block 33 arranged in the vertical direction, ECCinternal code (PI (Parity In) sign) 31 having 10 bytes data is affixedto the end of the data block 33 to constitute one correction block 34(refer to right side of FIG. 1B). At this stage, the correction blocks34 to which the ECC internal codes 31 are affixed are arranged in 12lines in the vertical direction. After that, this process is repeatedwith respect to 16 data sectors 20. Accordingly, the correction blocks34 of 192 lines are obtained.

[0041] Then, the correction blocks 34 of 192 lines are divided in thevertical direction from the beginning thereof, for each one byte, in thestate that the 192 lines of the correction blocks 34 are arranged in thevertical direction. 16 ECC external codes (PO (Parity Out) signs) 32 areaffixed to each of the vertically divided data blocks. It is noted thatthe ECC external code 32 is also affixed to a portion of the ECCinternal code 31 within the correction block 34.

[0042] From the above mentioned process, one ECC block 30 including 16data sectors 20 is produced as shown in FIG. 1B (right side). At thistime, a total amount of the information included within one ECC block 30is expressed by an equation described below.

(172+10) bytes×(192+16) lines=37856 bytes

[0043] The actual data 24 (i.e., other than ECC codes) in it isexpressed by an equation described below.

2048 bytes×16=32768 bytes

[0044] In the ECC block 30 shown in FIG. 1B, data of one byte isindicated by [D#. *]. For example, [D1. 0] indicates the data of onebyte positioned at a first line and a zeroth column, and [D190. 170]indicates the data of one byte positioned at a 190th line and a 170thcolumn. Thus, the ECC internal codes 31 are positioned at 172nd to 181stcolumns, and the ECC external codes 32 are positioned at 192nd to 207thlines. The correction blocks 34 are consecutively recorded on the DVD-R.

[0045] The reason why the ECC block 30 is constituted so as to includeboth the ECC internal code 31 and the ECC external code 32, as shown inthe right side of FIG. 1B, is that the data arranged in the horizontaldirection in FIG. 1B is corrected by the ECC internal code 31 and thedata arranged in the vertical direction is corrected by the ECC externalcode 32. That is, it is possible to perform the error correction in boththe horizontal and vertical directions within the ECC block 30 shown inFIG. 1B. Thus, the effective and stable error correction can beperformed as compared with the error correcting process used in theconventional CD (Compact Disk) and the like.

[0046] More concretely, for example, even if a certain one of thecorrection blocks 34 (as mentioned above, consecutively recorded on theDVD-R and each totally having the data of 182 bytes including the ECCinternal codes 31 for one line) is entirely broken by defect and thelike existing on the DVD-R, it is merely the one-byte data break withrespect to the ECC external codes 32 at one column, as viewed in thevertical direction. Thus, by carrying out the error correction using theECC external codes 32 at each column, it is possible to appropriatelycarry out the error correction to restore the original correctinformation from the broken information, even though one correctionblock 34 is entirely broken.

[0047] The manner of actually recording on the DVD-R the data sectors 20included in the ECC blocks 30 shown in FIG. 1B is explained withreference to FIG. 2. In FIG. 2, the data indicated in [D#. *]corresponds to the data described in the right side of FIG. 1B.

[0048] In recording the ECC blocks 30, on the DVD-R, the ECC blocks 30are firstly aligned along one line in a horizontal direction for eachcorrection block 34, as shown in a top stage of FIG. 2, and then areinterleaved to be divided into 16 recording sectors 40. At this time,one recording sector 40 includes information of 2366 bytes (=37856bytes/16), and the data sectors 20 and the ECC internal codes 31 and theECC external codes 32 are included in the manner being mixed with eachother in the recording sector 40. However, the ID information 21 (referto FIG. 1A) in the data sector 20 is positioned at a head portion ofeach recording sector 40.

[0049] The recording sector 40 is divided into a plurality of data 41each having 91 bytes, and a header H is added to each data 41. Afterthat, one sync frame 42 is produced from one data 41 by 8-16-modulatingthe recording sector 40 including the pairs of the header H and the data41. At this time, one sync frame 42 is composed of a header H′ and data43. Further, an information amount within one sync frame 42 is expressedby an equation described below.

91 bytes×8×(16/8)=1456 bytes

[0050] Then, the information is written to the DVD-R 1 in a form of thecontinuous sync frames 42. At this time, one recording sector 40includes 26 sync frames 42.

[0051] By constituting the above explained physical format to record theinformation on the DVD-R, the 8-16-demodulation and de-interleave (referto FIG. 2) are performed at the time of reproducing the recordedinformation to thereby reproduce the original ECC block 30 and toperform the effective error correction to accurately reproduce theinformation.

[0052] (II) Embodiment of Information Recording Apparatus

[0053] Next, an embodiment of an information recording apparatus, inaccordance with the present invention, for recording information on theDVD-R 1 according to the physical format explained with reference toFIGS. 1 and 2 is explained with reference to FIGS. 3 to 7. Here, thefollowing assumptions are made in the embodiment described below. Thatis, in the DVD-R 1, pre-pits carrying address information on the DVD-R 1and the like are formed in advance on the information tracks, on whichthe record information is to be recorded. Then, in recording the recordinformation, the address information on the DVD-R 1 is obtained bydetecting the pre-pits. By this, a record position on the DVD-R 1 wherethe record information is to be recorded is detected, and then therecord information is recorded.

[0054] A configuration of the information recording apparatus inaccordance with the present invention is firstly explained withreference to FIG. 3.

[0055] As shown in FIG. 3, an information recording apparatus S of theembodiment is provided with a pick-up 2, a reproduction amplifier 3, adecoder 4, a pre-pit signal decoder 5, a spindle motor 6, a servocircuit 7, a processor 8, an encoder 9, a switch 10, a power controlcircuit 11 and a laser drive circuit 12.

[0056] Next, a whole operation is explained.

[0057] The pick-up 2 includes a laser diode, a deflection beam splitter,an objective lens, light detectors and the like (not shown), andirradiates a light beam B onto the information record surface of theDVD-R 1 on the basis of a laser drive signal S_(DL), and detects thepre-pits on the basis of a reflected light thereof to thereby record therecord information. Moreover, in a case of the existence of old recordinformation that has already been recorded, the pick-up 2 detects theold record information on the basis of the reflected light of the lightbeam B.

[0058] Then, the reproduction amplifier 3 amplifies a detection signalS_(DT) including the pre-pits outputted by the pick-up 2 and theinformation corresponding to the old record information that has alreadybeen recorded, outputs a pre-pit signal S_(PP) corresponding to thepre-pits, and also outputs an amplification signal S_(P) correspondingto the old record information.

[0059] After that, the decoder 4 applies the 8-16-demodulation and theinterleave to the amplification signal S_(P) to thereby decode theamplification signal S_(P) and then outputs a demodulation signal S_(DM)and a servo demodulation signal S_(SD).

[0060] On the other hand, the pre-pit signal decoder 5 decodes thepre-pit signal S_(PP) to thereby output the demodulation pre-pit signalS_(PD).

[0061] The servo circuit 7 outputs a pick-up servo control signal S_(SP)for focus servo control and tracking servo control in the pick-up 2, onthe basis of the demodulation pre-pit signal S_(PD) and the servodemodulation signal S_(SD), and also outputs a spindle servo signalS_(SS) for servo-controlling the rotation of the spindle motor 6 forrotating the DVD-R 1.

[0062] Along with this, the processor 8 temporally stores and outputs arecord information signal S_(R) corresponding to the record informationthat is inputted from an external portion, and also outputs to theexternal a reproduction signal S_(OT) corresponding to the old recordinformation on the basis of the demodulation signal S_(DM), and furtheroutputs a switch signal S_(SW) described later, on the basis of thedemodulation pre-pit signal S_(PD).

[0063] The encoder 9 affixes the ECC internal code 31 and the ECCexternal code 32 to the record information signal S_(R) to therebyconstitute the ECC block 30, and also applies the interleave and the8-16-modulation to the ECC block 30 to thereby output an encode signalS_(RE).

[0064] At this time, the switch 10 switches between the encode signalS_(RE) and a ground signal to thereby output as an output signal S_(PC).

[0065] Then, the power control circuit 11 outputs a drive signal S_(D)for controlling an output of the laser diode (not shown) within thepick-up 2 on the basis of the output signal S_(PC).

[0066] After that, the laser drive circuit 12 actually drives the laserdiode on the basis of the drive signal S_(D) to thereby output a laserdrive signal S_(DL) for emitting the light beam B.

[0067] Further, the information recording apparatus S may reproduce theinformation recorded on the DVD-R 1. In that case, the reproductionsignal S_(OT) is outputted to the external through the processor 8 onthe basis of the demodulation signal S_(DM).

[0068] An operation for finishing the recording of record informationand an operation for starting the additional recording of new recordinformation, according to the present invention, are explained withreference to FIGS. 4 to 7, with classifying the cases.

[0069] (III) First Embodiment of Information Recording Operation

[0070] The first embodiment of the recording operation of the recordinformation is firstly explained with reference to FIGS. 4 and 5.

[0071] In the information recording operation of the first embodiment,when the recording of old record information (hereinafter referred to as“old data”) is finished, old dummy information (hereinafter referred toas “old dummy data”) 44 having an information amount corresponding totwo sync frames 42 is recorded, with an ID information 21 at a headportion, subsequent to the old data. When the additional recording ofnew record information (hereinafter referred to as “new data”) isstarted, new dummy information (hereinafter referred to as “new dummydata”) 45 having the same content as the old dummy data 44 is firstlyrecorded (i.e., overwritten) on an area corresponding to the second syncframe 42 of the areas on which the old dummy data 44 is previouslyrecorded. At this time, a data amount of the new dummy data 45 isdetermined in such a way that a total data amount of the remainder ofthe old dummy area after the additional recording of the new dummy data45 and an area of the new dummy data 45 is equal to or less than thedata amount of a single recording sector 40. After that, the new datawhich is to be primarily recorded is recorded subsequent to the newdummy data 45.

[0072]FIG. 4 is a flow chart indicating the process of additionallyrecording information on the DVD-R. FIG. 5 shows the informationrecording manner of the DVD-R 1 before and after the new data isrecorded, according to the first embodiment of the information recordingoperation.

[0073] In FIGS. 4 and 5, it is assumed that the ID information 21 in thefinal recording sector 40 of the old data is recorded at the address N,and that the ID information 21 in the recording sector 40 of the olddummy data 44 is recorded at the address (N+1).

[0074] In the first embodiment of the information recording operation,as shown in FIG. 4, when the additional recording of the new data isstarted, the address N corresponding to the ID information 21 in therecording sector 40 of last old data is searched (Step S1). Thisoperation is performed by the processor 8, on the basis of thedemodulation signal S_(DM) supplied from the decoder 4.

[0075] When the ID information 21 corresponding to the address N isdetected, the old data recorded on a recording sector 40 subsequent tothe detected ID information 21 is detected (Step S2). Then, it is judgedby the processor 8, on the basis of the demodulation signal S_(DM) fromthe decoder 4, whether or not the ID information 21 corresponding to theaddress (N+1) is detected (Step S3). If the ID information 21corresponding to the (N+1) is not detected yet (Step S3; NO), thedetection of the old data is continued until it is detected. If it isdetected, (Step S3; YES), the new dummy data 45, which contents is [0000. . . ], for example, having an information amount corresponding to:

[0076] (one recording sector—one sync frame)

[0077] is supplied from the processor 8 to the encoder 9 to betemporarily stored therein. Then, a record information signal S_(R)corresponding to new record information to be recorded subsequent to thenew dummy data 45 is supplied to the encoder 9, which encodes it andtemporarily stores the encoded data therein (Step S4).

[0078] At this time, an ECC block 30 for the new data may include thenew dummy data 45, or may not include it, i.e., the ECC block 30 for thenew data begins from an end position of the new dummy data 45 and iscomposed of only new data.

[0079] Next, old dummy data 44 (for example, [0000 . . . ]) recordedsubsequent to the ID information 21 corresponding to the address (N+1)is detected, and header H at the head portion of each sync frame 42 isdetected on the basis of the demodulation signal S_(DM) supplied fromthe decoder 4. Then, it is judged by the processor 8 whether or not thearea corresponding to a second sync frame 42 is detected in the area ofthe old dummy data 44 (Step S5). If the area corresponding to the secondsync frame 42 is not detected yet (Step S5; NO), the detection of theold dummy data 44 is continued until it is detected. If it is detected(Step S5; YES), the switch 10 is changed over to the terminal A sidethereof, on the basis of the switch signal S_(SW) from the processor 8.By this, the new dummy data 45 temporarily stored in the encoder 9 andnew data subsequent thereto are read out as the encode signal S_(RE),and then are outputted as the output signal S_(PC) via the switch 10(Step S6). Accordingly, the new dummy data 45 and the new datasubsequent thereto are recorded on the DVD-R 1 by means of the lightbeam B emitted from the pick-up 2.

[0080] The power of the light beam B is maintained to be a constantreproducing power, until the switch 10 is changed over to the terminal Aside, as shown in FIG. 5. After the switch 10 is changed over to theterminal A side (on and after the position corresponding to the headportion of the second sync frame 42 in the area of the old dummy data44), the power of the light beam is repeatedly switched between therecording power and the reproducing power in correspondence with thecontents of the new dummy data 45 included in the output signal S_(PC)and the new data subsequent thereto. The reason why the emission of thelight beam B is continuously kept at the reproducing power even when thedata is not recorded is that the reflected light used for the trackingservo control is required in order to permit the light beam B to tracethe information track on the DVD-R 1, even if the data is not recordedthere.

[0081] At the step 6, when the switch 10 is changed over to the terminalA side and thereby the new dummy data 45 and the new data are recorded,it is judged by the processor 8 whether or not the new data from theencoder 9 ends (Step S7). If it does not end (Step S7; NO), therecording of the new data is continued while maintaining its originalstate. If the new data ends (Step S7; YES), the dummy data (for example,[0000 . . . ]) having an information amount corresponding to two syncframes 42 is outputted by the encoder 9 and recorded subsequent to thelast new data (Step S8). When the recording of the dummy data isfinished, the switch 10 is changed over to the terminal B side (i.e.,the ground side), and the power of the light beam B is changed to thereproducing power (Step S9). By this, the additional recording processfor the new data is completed.

[0082] In the above mentioned process shown in FIG. 4, the new data isrecorded subsequent to the new dummy data 45 as shown in FIG. 5.Moreover, when the recording of the new data is finished, the dummy datais recorded, for the information amount corresponding to two sync frames42, subsequent to the new data thus recorded (the old data in FIG. 5have been recorded previously by this operation), and then the processis finished. The additional recording of the record information isperformed by repeating the above mentioned process. However, in thiscase, as for the state of the DVD-R 1 at the linking portion between theold data and the new data, the dummy data ([0000 . . . ]) is recordedfor the information amount equal to or less than one recording sector40, as shown in the lowest stage of FIG. 5. Here, in a portion where theold dummy data 44 and the new dummy data 45 are overlapped with eachother (this is the information amount corresponding to the one syncframe 42 and indicated as the data broken area D (hatched area) in FIG.5), both of the old dummy data 44 and the new dummy data 45 may bebroken due to the overwriting of the new dummy data 45. However, in thecase of consecutively reproducing the old data and the new data later,it is known that the dummy data at a boundary between the old data andthe new data is [0000 . . . ], even if the data in the D is broken.Therefore, by replacing the data detected from the data broken area Dwith the known data [0000 . . . ], it is possible to perform theconsecutive reproduction without disturbing the error correction in theconsecutive reproduction (without deteriorating the error correctingperformance in the consecutive reproduction).

[0083] In this embodiment, the dummy data is recorded for the dataamount corresponding to at most only one recording sector 40. As aresult, it is possible to record more record information by effectivelyusing the recording capacity of the DVD-R 1, as compared with a case ofproviding a linking area for one ECC block 30 in the conventionalmanner.

[0084] Moreover, the ID information 21 (at the address (N+1))corresponding to the recording sector 40 positioned at the linkingportion between the old data and the new data is never broken because nooverwriting is executed on the ID information area 21 (see. address(N+1) in FIG. 5). As a result, it is possible to accurately perform theconsecutive reproduction of the recorded information.

[0085] (IV) Second Embodiment of Information Recording Operation

[0086] The second embodiment of the recording operation of recordinformation is explained with reference to FIGS. 6 and 7.

[0087] In the information recording operation of the second embodiment,similarly to the first embodiment, old dummy data 44 of an informationamount corresponding to two sync frames 42 is recorded, with an IDinformation 21 at the head portion, subsequent to the recordinformation.

[0088] On the other hand, at the time of the additional recording of newdata, the recording is started from the second sync frame of new data,i.e., new data corresponding to first one sync frame 42 is removed fromthe beginning of the new data.

[0089]FIG. 6 is a flow chart indicating the operation of additionalrecording of the new data after the old data which has already beenrecorded. FIG. 7 shows the recording manner of the DVD-R 1 before andafter the new data is recorded by the second embodiment of theinformation recording operation.

[0090] In FIGS. 6 and 7, it is assumed that the ID information 21 in thefinal recording sector 40 of the old data is recorded at the address N,and that the ID information 21 in the recording sector 40 of the olddummy data 44 is recorded at the address (N+1). Moreover, the identicalstep numbers are given to the operations identical to those of the firstembodiment of the information recording operation shown in FIG. 4, andthe explanation of the detailed portions is omitted for those steps.

[0091] In the second embodiment of the information recording operation,as shown in FIG. 6, when the additional recording of the new data isstarted, the operations identical to the steps S1 to S3 shown in FIG. 4are firstly executed. Then, the ID information 21 at the head portion ofthe area of the old dummy data 44 is detected.

[0092] If the ID information 21 corresponding to the address (N+1) isdetected (Step S3; YES), a record information signal S_(R) correspondingto the new record information to be recorded is outputted, withoutinserting the dummy data, from the processor 8 to the encoder 9, whichencodes the new data and temporarily stores the encoded data therein(Step S10).

[0093] After that, the operations identical to those of the steps S5 toS9 shown in FIG. 4 are executed. New data from the second sync frame(i.e., after new data of first one sync frame 42 is removed from thebeginning of the new data) is recorded from the position correspondingto the second sync frame 42 of the area of the old dummy data 44. Whenthe all new data is recorded, dummy data of an information amountcorresponding to two sync frames 42 is recorded subsequent to the newdata. Then, the recording of the new data ends.

[0094] The power of the light beam B is maintained to be a constantreproducing power, until the switch 10 is changed over to the terminal Aside, as shown in FIG. 5. After the switch 10 is changed over to theterminal A side (on and after the position corresponding to the headportion of the second sync frame 42 in the area of the old dummy data44), the power of the light beam is switched between the recording powerand the reproducing power in correspondence with the contents of the newdummy data 45 included in the output signal S_(PC) and the new datasubsequent thereto.

[0095] According to the above mentioned process shown in FIG. 6, at thetime of the additional recording of the new data, the recording isperformed from the new data of second sync frame, i.e., the new datafrom which first one sync frame 42 thereof is removed from itsbeginning, as shown in FIG. 7. Moreover, when the recording of the newdata is finished, the dummy data is recorded for the information amountcorresponding to two sync frames 42, subsequent to the new data thusrecorded (like the manner of old data shown in FIG. 7). In this way, theprocess is finished. The additional recording of the record informationis performed by repeating the above mentioned process.

[0096] In this case, as for the state of the DVD-R 1 at a linkingportion between the old data and the new data in the additionalrecording, data different from the new data is recorded in a portion offirst two sync frames 42 from the beginning of the new data, as shown inthe lowest stage of FIG. 7. That is, the old dummy data 44 is recordedat the first one sync frame 42, and the second sync frame 42 subsequentto it becomes the data broken area D (hatched area). However, in thecase of the consecutive reproduction of the old data and new data, sinceboth the ECC blocks of the old data and the new data have the structuresof the ECC blocks 30 shown in FIG. 1, the data amount of the two syncframes 42 corresponds to the one correction block 34 in the ECC block30. Thus, as mentioned in the explanation of the ECC block 30, accordingto the structure of the ECC block 30 in which the error correction isperformed in both the vertical and horizontal directions using the ECCinternal code 31 and the ECC external code 32, even if one correctionblock 34 is entirely broken, it is only the data break of one byte forthe ECC external code 32 at one column as viewed in the verticaldirection. Therefore, by carrying out the error correction using the ECCexternal code 32 at each column, it is possible to appropriately carryout the error correction for the two sync frames 40 (i.e., onecorrection block 34) to thereby perform the accurate reproduction. As aresult, the consecutive reproduction can be performed without havingsubstantial influence on the error correction.

[0097] Further, the total data amount of the dummy data area and thedata broken area D is at most equal to two sync frames 42, this may notput any substantial influence on the error correction in the consecutivereproduction. Therefore, the consecutive reproduction can be performedwithout providing relatively large linking area between the old data andthe new data (the dummy area becomes a meaningless area in theconsecutive reproduction of the old data and the new data). As a result,it is possible to record more information by effectively utilizing therecord area on the DVD-R 1, as compared with the case of providing thelinking area corresponding to one ECC block 30 in the conventionalmanner.

[0098] Further, the second embodiment provides more improved use of datacapacity of the DVD-R 1, compared with the first embodiment. In thefirst embodiment, the dummy data is recorded in first one recordingsector 40 beginning from the address (N+1), and hence one recording area40 is used entirely in vain (see. FIG. 5, lowest stage). In contrast,according to the second embodiment, the recording sector 40 beginningfrom the address (N+1) is recorded with new data, and even though thedata brake takes place there, the broken data can be corrected by theECC function as described above. Therefore, no recording sector isvainly filled with dummy data in the second embodiment, and the datarecording efficiency is further improved.

[0099] Furthermore, the ID information 21 (corresponding to the address(N+1)) in the recording sector 40 at the linking portion of the old dataand the new data is never broken because, in either of the first and thesecond embodiments, no data is overwritten on the ID information 21 atthe address (N+1). As a result, the consecutive reproduction is notsuffered by the lack or break of the ID information 21, thereby enablingthe stable consecutive reproduction.

What is claimed is:
 1. An information recording method comprising thesteps of: applying a predetermined processing to record informationdivided into error correction units and generating processed recordinformation comprising a plurality of record units; recording theprocessed record information on an information record medium; andrecording, after the recording of the processed record information,predetermined dummy information for an information amount correspondingto the plurality of record units, on the information record medium,subsequent to the processed record information recorded.
 2. A methodaccording to claim 1, further comprising the step of overwriting dummyinformation comprising the steps of: detecting a head position of an olddummy information previously recorded on said information record medium;recording new dummy information on said information record medium, basedon the detected head position, such that a total information amount ofthe old dummy information after the recording of the new dummyinformation and the new dummy information recorded is no more than aninformation amount of one error correction unit.
 3. A method accordingto claim 2, wherein said processed record information recording stepfurther comprising the step of recording new record information on saidinformation recording medium from a position subsequent to the new dummyinformation recorded.
 4. A method according to claim 2, wherein saiddummy information recording step records the new dummy information overa part of the old dummy information previously recorded.
 5. A methodaccording to claim 1, wherein said processed record informationrecording step comprising the steps of: detecting a head position of thedummy information previously recorded on said information record medium;determining a recording start position from which new record informationis recorded on the basis of the detected head position of the dummyinformation and an information amount in a single error correction blockwhich is a minimum information unit of error correction; calculating aninformation removal amount corresponding to an information capacity inan area from the head position to the recording start position; removingthe record information corresponding to the calculated removal amountfrom a head of the record information to be recorded so as to produce anactual record information; and recording the actual record informationfrom the recording start position onto said information recordingmedium.
 6. A method according to claim 5, wherein said recording startposition determining step determines the recording start position withinan area where the dummy information is previously recorded.
 7. Aninformation recording apparatus comprising: means for applying apredetermined processing to record information divided into errorcorrection units and generating processed record information comprisinga plurality of record units; means for recording the processed recordinformation on an information record medium; and means for recording,after the recording of the processed record information, predetermineddummy information of an information amount corresponding for theplurality of record units, on said information record medium, subsequentto the processed record information recorded.
 8. An apparatus accordingto claim 7, further comprising means for overwriting dummy informationcomprising: means for detecting a head position of an old dummyinformation previously recorded on said information record medium; andmeans for recording new dummy information on said information recordmedium, based on the detected head position, such that a totalinformation amount of the old dummy information after the recording ofthe new dummy information and the new dummy information recorded is nomore than an information amount of one error correction unit.
 9. Anapparatus according to claim 8, wherein said processed recordinformation recording means further comprising means for recording newrecord information on said information recording medium from a positionsubsequent to the new dummy information recorded.
 10. An apparatusaccording to claim 7, wherein said dummy information recording meansrecords the new dummy information over a part of the old dummyinformation previously recorded.
 11. An apparatus according to claim 7,wherein said processed record information recording means comprising:means for detecting a head position of the dummy information previouslyrecorded on said information record medium; means for determining arecording start position from which the new record information isrecorded on the basis of the detected head position of the dummyinformation and an information amount in a single error correction blockwhich is a minimum information unit of error correction; means forcalculating an information removal amount corresponding to aninformation capacity in an area from the head position to the recordingstart position; means for removing the record information correspondingto the calculated removal amount from a head of the record informationto produce an actual record information; and means for recording theactual record information from the recording start position onto saidinformation recording medium.
 12. An apparatus according to claim 11,wherein said recording start position determining means determines therecording start position within an area where the dummy information ispreviously recorded.